The present invention relates in general to the field of flame retardants. More particularly, the present invention relates to flame retardant cellulose acetate.
Cellulose acetate is the acetate ester of cellulose. Cellulose acetate is prepared through the esterification of acetic acid with cellulose. Cellulose acetates with different properties are obtained depending on the degree of substitution. The reactivity of the cellulose may be uneven. The D-glucose unit is the fundamental repeating structure of cellulose and has three hydroxyl groups which can react to form acetate esters. The most common form of cellulose acetate flake has an acetate group on approximately two of every three hydroxyls. This cellulose diacetate is known as secondary acetate, or simply as “acetate”.
Cellulose acetate is partially or completely acetylated cellulose that contains acetyl (C2H3O) groups. Cellulose acetate is a straight chain polymer. The multiple hydroxyl groups on the glucose from one chain form hydrogen bonds with oxygen atoms on the same or on a neighbor chain, holding the chains firmly together side-by-side and forming microfibrils. Many properties of cellulose acetate depend on its chain length or degree of polymerization (e.g., the number of glucose units that make up one polymer molecule).